Thank you @JULES1111. Yes, the modular stair placement seems to be a bug (no stages in the ones I was trying to build) not allowing a lot to convert to apartment base seems to be a problem in M&G being installed. Not because it doesn't allow them but it has to do with floor tile and how many spaces M&G sees open above modular stairs.
I built apartments before without any trouble converting before M&G. It is one reason I put off ever installing M&G years ago. (due to it doesn't see enough space left open above staircases which is perfectly fine if it remains a residential lot). 4 spaces for residential, six to seven spaces above stairs if you have M&G installed. That ruins lay out of design sometimes, but I did test all this last night, lol, and drove myself crazy until it finally converted. M&G seems to be the problem about spaces over stair cases and can't place modular stairs if a wall is already built. :s Just in case someone else runs into these sort of problems.
Don't know how I'm going to solve the mailbox issue this is new and probably the buyable mailbox in my downloads/not on the lot it was a reg. Maxis one, since removing it from downloads didn't fix things for it, but made things worse since it's in German or Russian or something and I can't understand the language. It must have come in a lot I downloaded.
ETA: @Jules111, I just rechecked and yes, the one in my downloads is the bad one SEDD_BuyMailboxBV.package...I guess I try to find the AL one. thanks!!! You are awesome!!!
ETA: Found it for AL so my game will work again (I hope)!
Scroll down to download (small print) and replace the BV mailbox and other related files (see notes).
http://daydream.etowns.net/
